This invention pertains to scaffolds, and more particularly to a diesel powered, hydraulically actuated, mobile and adjustable scaffold system which provides a work bearing surface adjustable in all dimensions and adapted, among other uses, to the placement of massive roofing tile panels and panel grids in tunnels. Although it should be understood that this invention has several uses, including roofing and siding installations both above and below ground, the discussion which follows will illustrate its use in the context of placing roof tiles in highway tunnels.
In building road tunnels, existing techniques that involve the placement of tiled roof panels typically require that each panel be placed individually. The individual placement of such panel tiles, each of which may be up to four feet by ten feet in dimension and weigh in excess of 200 pounds is time consuming and expensive. Those existing devices that comprise self-propelled, mobile powered vehicles to set roof sections in place, or to set a roof, typically are designed for, and must be used in, specific and pre-determined means and methods of construction. These pre-determined means and methods may require that the mobile device itself be mounted on tracks, or may require that it extrude a more or less continuous ceiling layer. Further, such devices are typically limited to the single purpose kind of operation for which they were designed, are relatively specialized, and not easily adaptable for different construction modes or methods.
The preferred embodiment of this invention provides a work bearing surface that is approximately 18 feet by 30 feet, and which can lift up to 20,000 pounds. The work bearing surface of this invention is mobile and adjustable in all dimensions.
It is an object of the present invention to provide a mobile, self-powered and self contained machine that permits workers easily, safely and rapidly to pre-assemble an entire grid of roof panel tiles on the ground (or on the work bearing surface of the system itself), to transfer the pre-assembled grid of roof panel tiles onto the work bearing surface of the system, and to lift and guide the pre-assembled grid into place, aligning the new grid section precisely in all dimensions so as to assume the exact position required. The position of the new grid section delivered by the device of the present invention may be set relative to roof sections already in place, or according to desired specifications.
It is a further object of this invention to provide a highly mobile and extremely versatile scaffolding system inasmuch as it may be driven under its own power and readily maneuvered about the job site. All of its component assemblies and sub-assemblies operate individually and each of them can perform a different function. Further, the present invention is fabricated of non-specialized parts and so is easily maintained and serviced.
Using this invention for placing a roof in a tunnel, for example, an operator can lift massive single pieces, or can have a crew assemble grids of tunnel ceiling tiles either (a) on a frame on the ground, and then lift the frame onto the work bearing surface of the top table of the system for placement, or (b) on the work bearing surface of the top table of the system itself. As a result, tile can be placed faster, more efficiently and more cheaply than could be done without this invention. Further, the system is mobile, reusable and almost infinitely adjustable. The system is relatively easy to maintain because it uses standard parts and components, it is easy to drive and operate because it never needs to be backed up and because all four wheels steer, it is relatively inexpensive when compared to other mobile tunnel roofers, and it is more efficient than laying the ceiling tiles one by one. Other significant improvements afforded by this invention will be easily understood in connection with the detailed description of the system.
Accordingly, the present invention is a system which addresses problems of scaffolding generally, and of tunnel roofing in particular, providing a faster, more accurate and more efficient means of placing panel tiles and grids of panel tiles, and providing a more mobile, more versatile, and more readily maintained and serviced means of doing so than previously available.